Sulfuric-acid concentration



J. PATTEN.

SULFURIC ACID CONCENTRATION.

APPLICATION FILED DEC.30.1918.

Patented May 18, 1920.

UNITED STATES agent!) OFFICE.

com: ram-ran, or mim'moan, MARYLAND, Assrenon or ONE-HALF 'ro SAMUEL M.

' snoamnxna, or nconasron', MARYLAND.

SULFURIC-ACID CONCENTRATION.

Specification of Letters Patent.

Patented May 18, 1920.

Original application filed October 24, 1917, Serial No. 198,324. Patent No. 1,294,827, dated February 18,

. 1919. Divided and this application filed December 30. 1918. Serial No. 268,872.

To all whom it may concern:

Be it known that I, JOHN PA'rrnN, a citizen of the United States, and a resident of Baltimore, in the county of Baltimore and State of Mar land, have invented certain new and usef iil Improvements in Sul furic-Acid Concentration; and I do hereby declare the followin to be a full, clear, and exact description 0? the invention, such as will enable others skilled in the art vto which it appertains to make and use the same.

This invention relates to improvements in sulfuric acid concentration, this a plication being a division of application or patent filed by me on the 24th da of October, 1917, and designated by Serial 0.. 198,324.

My invention has reference to what is known as the cascade system and one object of the invention is to so manipulate such a system that while the concentrators are working continuously, the scale or sedimentof iron and other sulfates which accumulate in the concentrators (particularly those at and near the discharge end of a series of concentrators) will be periodically removed.

A further object is to provide means whereby the containers or concentrators may be cleaned and incrustation and sediment removed without necessity for removing or dismembering said concentrators.

With these and other objects in view the invention consists in certain features as hereinafter set forth and pointed out in the .claims.

concentrators at and near the discharge end of the series, because when the acid reaches these concentrators, most of the water has been evaporated from the acid and the minerals will no longer be held in solution but will be precipitated and form an incrustation which will act as insulation. These concentrators therefore become overheated and crack or break and discharge the acid mto the fire where it will damage the foundations and form larger volumes of sul- 'fur dioxid (S0 and other gases, which constitute a nuisance in the nei hborhood of the plant, and also result in t e loss of a large part of the acid, as well as an in- ,terruptlon 1n the operation of the plant.

culties heretofore experienced and to efi'ectually clean the concentrators of sediment. and incrustation without removing said concentrators or even opening them, and without stopping the operation of the plant.

In the apparatus shown in the drawing, 1 represents a furnace, for supplying heat under a connected series of communicating concentrators 2,-said series of concentrators being inclined and so disposed with respect to the furnace flues, that the greatest heat will be applied to the end of the series into which the acid is fed, as fully explained in my application for patent hereinbefore identified.

At or near one'end of the apparatus, two tanks 3 and 4 are located and may be supplied with acid from pipes at 5 and 6 from suitable sources.

The tank 3 is intended to contain acid of a strength of from to 62 B., or comprising about eighty per cent. H 80, and twenty per cent. H O; said acid to be concentrated to approximately 66 Be. or to a higher degree. The tank 4 is intended to contain a weak chamber acid, containing approximately from thirty-four to thirtyseven per cent. of water. The tanks 3, 1 ma discharge over a deflector 7 to a pan 8 an from the latter, by means of a ipe 9 to the first of the concentrators 2. alves 10-11 control the flow of, acid from the tank 3 and valves 12-13 may be provided for controlling the flow of acid from the tank,4=. The valves 10, 12, 13 may be operated manually, but the valve. 10 may be concentrator of. theseries and discharges into a receiving tank 14, the latterheing provided with a water jacket 15, and the acid overflows through a spout 16 to a funnel 17 pivoted to said spout. The pivoted funnel 17 is thus adapted to be made to v discharge into one of funnels 18 or 19 communicating, respectively, with pipes 20, 21 and the latter are intended to conduct the acid to separate storage tanks not shown.

A pipe 22 may beprovided for the escape of steam and aqueous vapors fr om the concentrators to a drum 23.

@When the valves 12-13' are closed and the valves 10-1l open, acid will flow from the tank 3 to the concentrators and in passing through the latter it will be concentrated to approximately 66 B. .and this will be discharged from the receiving tank 14, from which it will pass through the funnels 17-18 and pipe 20 to the storage tank for highly concentrated acid. As nearly all the Water has been evaporated out of the acid by the time the latter reaches the dischar e end of the series of concentrators and saic acid is no longer capable of holding the minerals (sulfates) in solution, the concentrators at and near the discharge end of the series will become coated with inorustation, as previously explained. Withto dissolve and hence remove'such incrustation. This maybe accomplished by closing the valves 1011 and opening one or both of the valves 12-13, thus stopping the feed of acid from the tank 3 and starting the supply of weak chamber acid from the tank 4. When the valves are thus shifted, the operator will move the funnel 17 out of line with the discharge funnel 18 and he will move said funnei 17 to position to discharge acid to the funnel 19, so that the weaker acid may beconducted through the pipe 21 to the separate tank proyided for it. When the acid from the tank 1 passes through the concentrators as above described, it will dissolve the incrustation as previously explained and it will also be concentrated to tron]. to 62 Be, and will therefore contain sufiicient water (from 34 to 37 per cent. or as low as 20 per cent.) to dissolve the minerals and hold the same in solution, care being exercised not to run this weak acid through the concentrators at such a slow speed as might cause too great concentration to insure the dissolving and holding in solution of the minerals. The acid resulting from the cleaning process, may be conducted, in any suitable way from the storage tank to the tank 3 and again passed through the concentrators for the manufacture of 66 acid.

When the incrustation shall have been removed as above-explained, the operator may close the valves 1213 and then the apparatus may be operated for the concentration of the stronger acid from 3. As soon as 66 acid begins to ow from the receiving tank 14:, the operator will shift the funnel 17 so that this 66 acid will be conducted to the pipe 20 and to the storage tank provided to receive it. 7

By alternately passing strong and weak acid through the concentrators at proper speeds, the incrustation caused by the concentration of the stronger acid-to 66 B., will effectually be removed by the Weak acid, and the operation of the apparatus and the method will be a continuous one.

Having fully described my invention, what I claim as new'and desire to secure by Letters Patent, is 1- 1. The combination with a connected series of concentrators and means for heating the same, of two valved sources for feeding acid to one end of said series of concentrators, two receiving means for acid from the concentrators, and means for shifting the discharge of acid from one of said receiving means to the other.

2. In sulfuric acid concentration apparatus, the combination of a'connected series of concentrators and means for heating the same, of separate sources of weak and stronger acid for supplying acid to the concentrators, means for controlling theflow of acid from one or the other of such sources, two receiving means for acid from said concentrators, and means for directing acid into one or the other of the receiving means, whereby the apparatus may be operated I alternately to concentrate acid to a high de gree and operated to condense acid to a lesser degree and dissolve incrustatlon left by the first-mentioned concentration, and

whereby the acid resulting from the two concentrations may be separately recovered.

3. The Y combination with a connected series of concentrators and means for heating the same, of two valved sources for feeding acid to one end of said series of concentrators, two discharge pipes, a tunnel on each of said discharge pipes, a receiver for concentrated acid from the concentrators,

and a spout for conveying acid from the receiver-to the funnel on one or the otheigof said discharge pipes.

4. The combination with a connectedseries of concentrators and means for heating the same, of two valved sources for feeding acid to one end of the series of concentrators, a receiver at the other end of the series of concentrators, two receiving pipes for acid from said receiver, and adjustable means between said receiver and receiving pipes for causing the acid from the receiver to be directed to one or the other of said receiving pipes.

5 5. The combination with a connected series of concentrators, and means for heating the same, of two valved sources for feeding acid to one end of said series of concentrators, a receiver for concentrated acid at 10 the other end of the series of concentrators,

two discharge pipes, a funnel on each of said discharge pipes, a spout communicating with the receiver, and a funnel pivotally mo unted on said spout and adapted to be made to discharge into the funnel of either of the discharge pipes.

In testimony whereof I have signed this specification.

JOHN PATTEN. 

